The present invention relates to a multiple fuse device for a vehicle, which is intended to be mounted on a vehicle, which in use is housed in a fuse box, and which has a structure in which a battery-side bus bar portion and an alternator-side bus bar portion each including a plurality of input/output terminals via individual fusing portions are connected to each other by a fusing portion for charging current protection.
The multiple fuse device for a vehicle of the present invention is intended for use in a vehicle, and is applicable to the industrial field in which it is required to prevent a fusing portion for charging current protection from being deformed or broken during the device's assembly.
Multiple fuse devices for vehicles exist which have structures in which a battery-side bus bar portion, connected to a battery and including a plurality of input/output terminals via individual fusing portions, and an alternator-side bus bar portion, connected to an alternator and including a plurality of input/output terminals via individual fusing portions, are connected to each other by a fusing portion for charging current protection.
A thus-structured multiple fuse device for a vehicle has a fuse function for preventing overcurrent from flowing through the load equipment connected to the respective input/output terminals, which disconnects the circuit through the protection of the fusing portion for charging current if the charging current from the alternator to the battery becomes excessive. That is, the fusing portion for charging current protection connecting the battery-side bus bar portion and the alternator-side bus bar portion to each other is a portion indispensable for this fuse device.
Among the multiple fuse devices for vehicles such as those described above, the present invention is especially applied to a multiple fuse device which includes a circuit board for achieving a fuse function. This circuit board is made of copper alloy plate member, which is punched to create a battery-side bus bar portion, an alternator-side bus bar portion, a fusing portion for charging current protection, and the like. In this case, since all the circuitry shapes (circuitry patterns) including the fusing portions can be formed at one time, it is also advantageous in terms of cost.
An exemplary multiple fuse device for a vehicle such as described above is suggested in Japanese Laid-Open Patent Publication No. 2001-054223.
FIG. 7 of the present document shows a multiple fuse device for a vehicle that constitutes background art for the present invention.
FIG. 7 shows a circuit board 50 of the multiple fuse device for a vehicle that is described above. The circuit board 50 is formed by punching a copper alloy plate member to form a structure in which a battery-side bus bar portion 44 including a plurality of input/output terminals 42 via individual fusing portions 41 and an alternator-side bus bar portion 45 including a plurality of input/output terminals 42 via individual fusing portions 41 are connected to each other by a fusing portion 46 for charging current protection. The battery-side bus bar portion 44 includes a battery connection terminal 44a; the alternator-side bus bar portion 45 includes an alternator connection terminal 45a. 
The circuit board 50, having the structure described above, permits the above-described multiple fuse device to perform its function and have its effect. However, although the fusing portion 46 for charging current protection is a narrow and weak portion, it interconnects the battery-side bus bar portion 44 and the alternator-side bus bar portion 45, each of which includes a plurality of input/output terminals 42 and the like. There is a possibility that the fusing portion 46 for charging current protection may be deformed or broken during an assembly step in which the circuit board 50 is covered and insulated by an insulator housing. The same problem of deformation and breakage may possibly arise in the individual fusing portions 41.
However, the invention of Japanese Laid-Open Patent Publication No. 2001-054223 is intended to solve problems that resulted from contact failure and the increased size of the fuse device, and has no description as to the problem arising in the assembly, much less as to the means for solving such a problem. Japanese Laid-Open Patent Publication No. 2004-213906 suggests a multiple fuse device for a vehicle including the fusing portion for charging current protection and individual fusing portions, similarly to Japanese Laid-Open Patent Publication No. 2001-054223. However, in Japanese Laid-Open Patent Publication No. 2004-213906 as well, there is neither a recognition of such a problem nor a description as to means for solving such a problem.